That is the instruction for multiplying just one double (the SD suffix stands for scalar double); the respective instructions for handling more than one number

That is the instruction for multiplying just one double (the SD suffix stands for scalar double); the respective instructions for handling more than one number at the same time have a PD suffix (for packed double). The alternative would be to use the x87 FPU registers and instructions, which are a lot slower these days (but yes, also with different precision characteristics). So they're usually not used at all in code targeting x64.